Date Add Calculator

The Date Add Calculator is a powerful online tool for calculating future and past dates by adding or subtracting years, months, weeks, and days from any base date. It instantly shows the resulting date and day of the week, answering questions like "What date is 90 days from today?" or "What was the date 3 months ago?"

Enter negative values to calculate past dates. The tool automatically adjusts for leap years and month-end conditions — for example, adding 1 month to January 31 correctly yields February 28 or 29 depending on the year. Perfect for deadline calculation, contract end date verification, scheduling periodic checkups, reverse-calculating event dates, and managing warranty periods.

Combine multiple units simultaneously for compound calculations like "1 year, 2 months, and 3 days later" in a single step. The base date defaults to today, and you can set it with one click using the "Today" button. Quick preset buttons (+30 days, +90 days, +1 year, +3 months) speed up common calculations. Useful for managing long-term projects, confirming dates around calendar transitions, and date arithmetic in business planning.

Use [Days Between Calculator](/en/calc/days-between-calculator/) when you need the interval between two dates. Use [Working Days Calculator](/en/calc/working-days-calculator/) when only weekdays should count, and [Weekday Calculator](/en/calc/weekday-calculator/) when you only need the day of week. For text-based date comparisons, check [Date Diff Calculator](/en/text/date-diff-calculator/).